Vitamin Reference Guide
Most of us know vitamins are a critical part of our lives,
without which we would be left susceptible to numerous diseases
and unfavorable conditions. Many of us do not know, however,
why our bodies need particular vitamins. Furthermore, we are
unclear about how much of a vitamin to consume and in which
foods these essential vitamins can be found. This article
will analyze the five most important vitamins by providing
information on their functions, the effects of their deficiency
and/or excess, and a list of foods that contain each vitamin.
The most noticeable function of vitamin A is improvement
of night vision (our body’s ability to see in the dark). Internally,
this vitamin acts as a stimulus to the production of white
blood cells and a regulator of cell growth and division. It
also helps keep the lining of internal surfaces (endothelial
cells) healthy and aids in bone remodeling.
The recommended daily consumption of vitamin A is 4,000 IU
for women and 5,000 IU for men. Intake in excess of 10,000
IU may increase one’s risks of hip fractures and certain birth
Vitamin A can be found in cereal, dairy products, fruits,
The 3 B vitamins - B6, B12, and folic acid – allow the body
to turn homocysteine into methionine. There are two reasons
this process is important. First, since homocysteine is being
turned into methionine, homocysteine levels are kept low.
Secondly, the methionine that is produced is used in the body’s
production of proteins.
Although the recommended daily intake of vitamin B is constantly
changing, current suggestions are as follows:
B6: One should consume between 1.3 to 1.7 mg daily.
B12: 6 micrograms are recommended each day. A century ago,
B12 deficiency caused a deadly disease known as pernicious
anemia. Among the disease symptoms were memory loss, hallucinations,
and tingling limbs. This disease is rare today and usually
only affects elderly adults whose bodies are unable to absorb
this vitamin from food consumption.
Folic acid: 400 mg per day is recommended.
A deficiency in B vitamins slows the conversion of homocysteine
into methionine. A high level of homocysteine results, which
according to some studies, may increase one’s risk of heart
disease and stroke.
It is difficult to consume the recommended daily levels of
vitamin B through food alone. A daily multivitamin is recommended.
Vitamin C is responsible for controlling infections. It
also aids in the production of collagen, a tissue that is
necessary for healthy teeth, gums, and bones. Some studies
have even shown that taking vitamin C at the onset of a cold
helps alleviate some cold symptoms.
Women are advised to consume 75 mg while men should consume
90 mg daily. It is also suggested that smokers consume an
additional 35 mg of vitamin C.
Vitamin C can be found in many fruits and vegetables, including
berries, citrus fruits, broccoli, peppers (red and green),
spinach, and tomatoes. Some cereals also are enriched with
The human body uses vitamin D to aid in the absorption and
retention of calcium and phosphorous, two elements that are
essential for bone building and strength. Some studies have
also shown that vitamin D hinders cancer cells from growing
Persons under 50 should consume 5 micrograms of vitamin D
each day. Intake doubles to 10 micrograms for anyone between
51 and 70 and triples to 15 micrograms for anyone over 70.
A deficiency in vitamin D has been shown to increase the risk
of fractures and possibly increase the risk of breast, colon,
and prostate cancers.
Many cereals and dairy products are enriched with Vitamin
D. Vitamin D can also be found in salmon, tuna and other seafood
that is high in fat. A multivitamin is recommended since it
is difficult and unhealthy to obtain the required amounts
of vitamin D from these foods.
Vitamin K plays an important role in the body’s ability
to form blood clots. Producing six out of the thirteen proteins
needed for blood clotting, it is critical that the body receives
enough vitamin K each day. Recent studies have also shown
that vitamin K may also assist in keeping bones strong and
preventing hip fractures.
Women should consume 65 micrograms while men should consume
80 micrograms daily. Since many foods contain vitamin K, deficiency
is rare. Vitamin K deficiency is serious, however. Since the
body would be unable to form blood clots, a person could die
from blood loss due to uncontrollable bleeding.
Vitamin K can be found in many green leafy vegetables such
as broccoli, cauliflower, cabbage, and spinach. Canola, olive
and soybean oil also contain ample amounts of vitamin K.
Are you getting enough of these essential vitamins?
Track your daily food intake, being sure to keep track of
the amount of each vitamin contained in each food. At the
end of your day, compare each vitamin's total with the daily
recommendations outlined above.
If you are not getting enough of these vitamins through your
typical food consumption, consider taking a daily multivitamin
that contains the vitamins your body is lacking. Of course,
you should always consult your doctor or a nutritionist before
beginning taking any supplements.